Did Pippa Middleton try to upstage Duchess Kate once again?

Did Pippa Middleton upstage her sister, The Duchess of Cambridge at Princess Charlotte's christening? Photo: Getty Images

Pippa Middleton made headlines in 2011 when she stepped out wearing that dress at sister Kate Middleton's wedding to Prince William.

The 31-year-old became a household name - and was even dubbed 'Her Royal Hotness' - when her cream Alexander McQueen bridesmaid dress hugged her in all the right places.

This week, the royal sister-in-law appeared to have done it again, when she stepped out in a cream, long-sleeved frock by Emilia Wickstead and nude Charlotte Olympia pumps.

PHOTOS: 7 must-see photos from Princess Charlotte's christening

Some have accused the socialite of trying to 'upstage' The Duchess, who also opted for cream in her Alexander McQueen coat dress.

Both sisters wore headpieces by the same milliner, Jane Taylor.

“Pippa Middleton is the epitome of elegance and style,” Taylor, who has had a long-running relationship with the royals, told Us Weekly.

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Duchess Kate chose a Alexander McQueen frock for her daughter's christening at St Mary Magdalene church in Norfolk on July 5. Photo: Getty Images

“And I could not be more honoured to see her wearing one of my designs so beautifully today at such a significant royal occasion.”

Etiquette expert William Hanson says turning up in the same colour as the host of the event is a faux pas.

"If attending an event where you are on good terms with the host then asking what colour they are planning on wearing is good manners so you avoid clashing too much," he told the Daily Mail.

PHOTOS: The Middletons attend Princess Charlotte's christening

PHOTOS: The Middletons attend Princess Charlotte's christening. Photo: Getty Images

It would seem odd that the pair, who are believed to enjoy a close relationship, did not discuss their outfit choices before the event.

However Pippa also wore a similar outfit to Kate's back in 2013 at Prince George's christening so perhaps the sisters jsut simply don't care about such things...

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